The inventive concept relates generally to semiconductor memory devices, and more particularly, a nonvolatile memory device and an operating method for same.
Semiconductor memory devices may be classified as volatile memory devices such as DRAM and SRAM, and nonvolatile memory devices such as EEPROM, FRAM, PRAM, MRAM, flash memory, and the like. Unlike volatile memory devices, nonvolatile memory devices are able to retain stored data in the absence of applied power. Flash memory is a particularly popular type of nonvolatile memory as it provides fast programming speed, low power consumption, and large amounts of data storage.
A flash memory device may include memory cells configured to operate as single-level memory cells (SLC) capable of storing binary data, and/or multi-level memory cells capable of storing 2 or more bits of data per memory cell.
The additional data storage capacity provided by MLC flash memory comes at some operational burden. For example, it is important to secure adequate read margins between adjacent program states in a MLC flash memory device. However, MLC threshold voltages in flash memory device will vary due to various causes such as coupling noise, pass voltage disturbance, program voltage disturbance, and the like.